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An assessment of the airplane drag problem at transonic and supersonic speeds

Description: Report presenting the airplane drag problem at transonic and supersonic speeds. The area rule is shown to be a powerful tool that provides guidance for designers in selecting aerodynamic features compatible with low wave drag. Analytical methods have been developed that permit quantitative evaluation of the wave-drag level likely to be experienced with a given design.
Date: July 15, 1954
Creator: Donlan, Charles J.
Partner: UNT Libraries Government Documents Department

Large-Scale Flight Measurements of Zero-Lift Drag at Mach Numbers from 0.87 to 1.39 of 1/10-Scale Models of the Northrop MX-775A Missile

Description: A flight investigation was made at high subsonic, transonic, and supersonic speeds and at high Reynolds numbers to determine the zero-lift drag of a 1/10-scale model of the Northrop MX-775A missile and a scale model of the missile fuselage. The model of the complete configuration has a 45deg swept wing of aspect ratio 5.5 and a 33deg swept vertical fin. The body model was stabilized by three 45deg swept fins. The-drag-rise Mach number for the model of the complete configuration was approximately 0.96. The drag coefficient based on total wing area was 0.0330 at Mach number 1.39. The drag coefficient of the body model less fin drag was approximately 55 percent that of the complete model at the same Mach number. Addition of the wing to the fuselage apparently resulted in a favorable drag interference near Mach number 1.0.
Date: November 9, 1951
Creator: Gillespie, Warren, Jr. & Arbic, Richard G.
Partner: UNT Libraries Government Documents Department

Drag interference between a pointed cylindrical body and triangular wings of various aspect ratios at Mach numbers of 1.50 and 2.02

Description: The drag of a body alone, six triangular wings of various aspect ratios, and the combinations were measured at Mach numbers of 1.50 and 2.02 at a Reynolds number of 5.5 million (based on the body length). The experimental drag-interference results were in accordance with calculations based on NACA RM A9E19, 1949, with skin-friction effects taken into account, the interference effect being principally the result of fixing transition on the body by adding a wing.
Date: November 1956
Creator: Katzen, Elliott D. & Kaattari, George E.
Partner: UNT Libraries Government Documents Department

Drag interference between a pointed cylindrical body and triangular wings of various aspect ratios at Mach numbers of 1.50 and 2.02

Description: The drag of a body alone, six triangular wings of various aspect ratios, and the combinations were measured at Mach numbers of 1.50 and 2.02 at a Reynolds number of 5.5 million (based on the body length). The experimental drag-interference results were in accordance with calculations based on NACA RM A9E19, 1949, with skin-friction effects taken into account, the interference effect being principally the result of fixing transition on the body by adding a wing.
Date: May 23, 1951
Creator: Katzen, Elliott D. & Kaattari, George E.
Partner: UNT Libraries Government Documents Department

Performance of external-compression bump inlet at Mach numbers of 1.5 and 2.0

Description: Report presenting an experimental investigation of a scale model of the forebody of a proposed supersonic fighter to determine the internal performance and configuration drag of various twin-side inlets. External-compression ramp and bump inlets with various types and combinations of boundary-layer bleed were tested. Results regarding performance charts and flow characteristics are provided.
Date: April 24, 1957
Creator: Simon, Paul C.; Brown, Dennis W. & Huff, Ronald G.
Partner: UNT Libraries Government Documents Department

Drag determinations of the forward component of a tricycle landing gear

Description: Wind-tunnel tests were performed to determine the drag of the front-wheel arrangements of several types of tricycle landing gear. One wheel was tested in arrangements to simulate both nonretracted and partially retracted types. The landing gears were tested in conjunction with a fuselage, and the effects of wheel extension and longitudinal location were determined. The drag changed very little with either longitudinal location or wheel extension for the landing gear with the lowest drag; a completely faired landing gear of the wheelspan, single-strut type. The drag of the trouser-type landing gear increased considerably, however, with an increase in the wheel extension. The wheel of the unaired retractable landing gear was at least one-half retracted into the fuselage before the drag became less than that of the best nonretracted landing gear. The drag per unit frontal area of the landing gears of the present tests was about the same as that found for similar landing gears in earlier tests.
Date: December 1940
Creator: Harmon, Hubert N.
Partner: UNT Libraries Government Documents Department

Flight measurements of drag and base pressure of a fin-stabilized parabolic body of revolution (NACA RM-10) at different Reynolds numbers and at Mach numbers from 0.9 to 3.3

Description: From Summary: "Free-flight tests have been made to investigate the total drag and base drag at different Reynolds numbers of full-scale and half-scale models of an NACA research model designated the RM-10. The general shape of the body was a parabola of revolution of fineness ratio 12.2 with a blunt base to provide space for the rocket jet. The models were stabilized by four 60 degree sweptback fins mounted at the base of the bodies."
Date: November 1954
Creator: Jackson, H. Herbert; Rumsey, Charles B. & Chauvin, Leo T.
Partner: UNT Libraries Government Documents Department

High-Speed Tests of Conventional Radial-Engine Cowlings

Description: The drag characteristics of eight radial-engine cowlings have been determined over a wide speed range in the NACA 8-foot high-speed wind tunnel. The pressure distribution over all cowlings was measured, to and above the speed of the compressibility burble, as an aid in interpreting the force tests. One-fifth-scale models of radial-engine cowlings on a wing-nacelle combination were used in the tests.
Date: March 30, 1939
Creator: Robinson, Russell G. & Becker, John V.
Partner: UNT Libraries Government Documents Department

An investigation of the drag of windshields in the 8-foot high-speed wind tunnel

Description: Report presents the results of tests made to determine the drag of closed-cockpit and transport-type windshields. The tests were made at speeds corresponding to a Mach number range of approximately 0.25 to 0.58 in the NACA 8-foot high-speed wind tunnel. This speed range corresponds to a test Reynolds number range of 2,510,000 to 4,830,000 based on the mean aerodynamic chord of the full-span model (17.29 in.). The shapes of the windshield proper, the hood, and the tail fairing were systematically varied to include common types and refined design.
Date: May 22, 1939
Creator: Robinson, Russell G. & Delano, James B.
Partner: UNT Libraries Government Documents Department

Free-flight measurements of the zero-lift drag of several wings at Mach numbers from 1.4 to 3.8

Description: Report presenting the zero-lift drag of several wings obtained at supersonic Mach numbers in free flight with rocket-propelled models. The wings tested all had the same exposed area, mounted on the same basic body configuration, and had one of four different types of wings.
Date: June 22, 1956
Creator: Jackson, H. Herbert
Partner: UNT Libraries Government Documents Department

Supersonic aerodynamic characteristics of a low-drag aircraft configuration having an arrow wing of aspect ratio 1.86 and a body of fineness ratio 20

Description: Report presenting a free-flight rocket-propelled model investigation at Mach numbers from 1.2 to 1.9 to determine the longitudinal and lateral aerodynamic characteristics of a low-drag aircraft configuration. Aerodynamic data in pitch, yaw, and roll were obtained from transient motions induced by small pulse rockets firing at intervals.
Date: March 19, 1957
Creator: Gillespie, Warren, Jr.
Partner: UNT Libraries Government Documents Department

Supersonic wave drag of nonlifting delta wings with linearly varying thickness ratio

Description: Report presenting the supersonic wave draw of a nonlifting, symmetrical, double-wedge-profile, delta wing with a linearly varying thickness ratio as calculated by the use of linear theory. It was found that a delta wing with linearly varying thickness ratio can have less wave drag than a similar wing with a constant thickness ratio.
Date: December 1952
Creator: Henderson, Arthur, Jr.
Partner: UNT Libraries Government Documents Department

Effect of Nozzle Contour on Drag of Parabolic Afterbodies

Description: Memorandum presenting an investigation of the effect of nozzle internal contour on afterbody drag in the 8- by 6-foot supersonic wind tunnel. Five different nozzle-afterbody configurations were evaluated. Results regarding the boattail pressure drag, base drag, and total drag are provided.
Date: June 21, 1954
Creator: Vargo, Donald J. & Englert, Gerald W.
Partner: UNT Libraries Government Documents Department

Measurements of the effect of trailing-edge thickness on the zero-lift drag of thin low-aspect-ratio wings

Description: Report presenting an exploratory free-flight investigation at zero lift of several rocket-powered drag-research models with tapered 4-percent-thick wings for a range of Mach numbers. Results regarding the total-drag coefficient, wing drag coefficients, and drag-coefficient components are provided.
Date: November 1955
Creator: Morrow, John D.
Partner: UNT Libraries Government Documents Department

Investigation of the drag of various axially symmetric nose shapes of fineness ratio 3 for Mach numbers from 1.24 to 7.4

Description: Experimental drag measurements at zero angle of attack for various theoretical minimum drag nose shapes, hemispherically blunted cones, and other more common profiles of fineness ratios of about 3 are compared with theoretical results for a Mach number and Reynolds number range of 1.24 to 7.4 and 1.0 x 10 to the 6th power to 7.5 x 10 to the 6th power (based on body length), respectively. The results of experimental pressure-distribution measurements are used for the development of an empirical expression for predicting the pressure drag of hemispherically blunted cones.
Date: August 28, 1952
Creator: Perkins, Edward W.; Jorgensen, Leland H. & Sommer, Simon C.
Partner: UNT Libraries Government Documents Department

Some examples of the applications of the transonic and supersonic area rules to the prediction of wave drag

Description: Report presenting a comparison of the experimental wave drags of bodies and wing-body combinations over a wide range of Mach numbers with the computed drags utilizing a 24-term Fourier series application of the supersonic area rule and results of equivalent-body tests. The equivalent-body technique was found to provide a good method for predicting the wave drag of certain wing-body combinations at and below a Mach number of 1, but becomes misleading at Mach numbers greater than 1.
Date: March 20, 1957
Creator: Nelson, Robert L. & Welsh, Clement J.
Partner: UNT Libraries Government Documents Department

A theoretical and experimental investigation of the lift and drag characteristics of hydrofoils at subcritical and supercritical speeds

Description: From Summary: "A theoretical and experimental investigation at subcavitation speeds was made of the effect of the free-water surface and rigid boundaries on the lift and drag of an aspect-ratio-10 hydrofoil at both subcritical and supercritical speeds and of an aspect ratio-4 hydrofoil at supercritical speeds. Approximate theoretical solutions for the effects of the free-water surface and rigid boundaries on drag at subcritical speeds are developed. An approximate theoretical solution for the effects of these boundaries on drag at subcritical speeds is also presented. The agreement between theory and experiment at both supercritical and subcritical speeds is satisfactory for engineering calculations of hydrofoil characteristics from aerodynamic data. The experimental investigation indicated no appreciable effect of the limiting speed of wave propagation on lift-curve slope or angle of zero lift. It also showed that the increase in drag as the critical speed is approached from the supercritical range is gradual. The result is contrary to the abrupt increase at the critical speed predicted by theory."
Date: 1955
Creator: Wadlin, Kenneth L.; Shuford, Charles L., Jr. & McGehee, John R.
Partner: UNT Libraries Government Documents Department

Low speed yawed-rolling and some other elastic characteristics of two 56-inch-diameter, 24-ply-rating aircraft tires

Description: Report investigating the low-speed cornering characteristics of two 56 x 16, type VII, extra-high-pressure, 24-ply-rating tires for a range of vertical loadings, yaw angles, and tire inflation pressures. The quantities measured included cornering force, drag force, self-alining torque, pneumatic caster, vertical tire deflection, rolling radius, and relaxation length. Some supplementary testing included measurements of tire footprint area, vertical-load-deflection characteristics, and variation of tire radius and width with inflation pressure.
Date: August 1954
Creator: Horne, Walter B.; Stephenson, Bertrand H. & Smiley, Robert F.
Partner: UNT Libraries Government Documents Department

Comparison of the Drag of a Fin-Stabilized Body of Revolution and of a Complete Airplane Configuration as Obtained at Transonic Speeds in a Slotted Wind Tunnel and in Free Flight

Description: From Summary: "A comparison of the zero-lift drag coefficients at Mach numbers from 0.81 to 1.41 of a fin-stabilized parabolic body of revolution as measured in the Langley transonic blowdown tunnel has been made with measurements obtained in free-flight on a larger but geometrically similar model. The absolute values of drag coefficient obtained in the slotted wind tunnel were equivalent to the free-flight drag-coefficient values up to a Mach number of 1.4 when adjustments were made for the effect on viscous drag of differences in Reynolds number between the two test conditions. Excellent agreement was obtained between the two tests for the pressure-drag variation with Mach number, regardless of whether the scale effect on skin friction was considered."
Date: August 1955
Creator: Howell, Robert R. & Braslow, Albert L.
Partner: UNT Libraries Government Documents Department

Transonic free-flight investigation of the total drag and of the component drags (cowl pressure, additive, base, friction, and internal) encountered by a 16-inch-diameter ram-jet engine for Mach numbers from 0.80 to 1.43

Description: Report presenting an investigation of the drag on four full-scale models of 16-inch-diameter ramjet engines. The total, base, internal, and external drag were evaluated for each of the models. Results regarding the drag evaluations and drag comparison are provided.
Date: August 13, 1952
Creator: Messing, Wesley E. & Rabb, Leonard
Partner: UNT Libraries Government Documents Department

Comparison of zero-lift drags determined by flight tests at transonic speeds of symmetrically mounted nacelles in various chordwise positions at the wing tip of a 45 degrees sweptback wing and body combination

Description: Report presenting the effect on drag of varying the chordwise position of a nacelle at the wing tip of a 45 degree sweptback wing and body combination as determined through transonic flight tests at zero lift. The drag of the configuration with nacelles in the rear chordwise positions was equal to or less than the drag of the configuration without nacelles over most of the speed range.
Date: September 17, 1951
Creator: Pepper, William B., Jr. & Hoffman, Sherwood
Partner: UNT Libraries Government Documents Department